Breathing gas regulators of the second stage or the positive pressure demand type regulators are used by underwater divers as well as firemen and industrial workers. The breathing gas regulators allow for demand regulation when one inhales.
Such second stage positive pressure demand type regulators are generally connected to a source of breathing gas. The source of breathing gas can be a first stage regulator or high pressure regulator. The first stage or high pressure regulator is generally connected by a valve to a tank of highly pressurized breathing gas. The first stage demand regulator or high pressure regulator regulates the high pressure in the tank down to a pressure within the range of 150 pounds per square inch (psi). This lowered pressure of 150 psi is in connected relationship to a hose or other conduit that is then connected to the second stage or positive pressure demand regulator.
The second stage or positive pressure demand regulator has a mouthpiece or means to connect the regulator to a mask for breathing purposes. When inhalation takes place by one attempting to breathe, the second stage or positive pressure demand regulator actuates a valve to provide for the flow of breathing gas from the first stage regulator through the second stage for breathing purposes. This has been accomplished in the past by a diaphragm system.
The diaphragm generally moves upon inhalation, thereby tripping a valve mechanism such as a tilt valve or other type of lever in order to provide for valving the breathing gas. When the inhalation by a user is encountered, the diaphragm is displaced so as to cause the valve connected to it to open. This creates an upstream valve function by the first stage regulator to allow for the flow of gas on a demand basis.
When such regulators are used by firemen, industrial or safety workers, it is desirable to have a positive pressure to prevent the inflow of noxious gases. This is accomplished by either a free flow into a users mask or regulator, or in the alternative a positive pressure that is established.
In order to prevent inordinate amounts of air flow, a means for shutting off the regulator has been utilized in the past which can be actuated by inhalation. This invention specifically relates to such inhalation actuation as well as the specific pilot valve and valving functions hereof.
This invention is directly related to the concept of providing for a second stage regulator shut off override. The regulator can then be re-actuated by an initial first breath or inhalation to put the regulator back into a gas regulating function. The invention is specifically enhanced by virtue of a slide device which lifts a coupler attached to the diaphragm so as to place the diaphragm in an inoperative overridden or shut off mode. This slide device relies upon a spring biased coupler which can re-actuate the regulator by a negative pressure or inhalation against the diaphragm. This then allows the unique pilot and valving function of this invention to proceed with providing uniform and consistent action of the second stage regulator upon continued inhalation and breathing functions.
The regulator is also enhanced by a bypass valve and a particularly unique design for allowing the bypass valve to function independent of the main valve. The main valve is formed of an elastomeric balanced valve member on a valve seat. It is pilot valve operated by a levered toggle mechanism that allows the pilot valve to cause the main valve to function upon inhalation being encountered at the face of the diaphragm.
The inter relationship of the bypass valve, reactuating the override function, the pilot valve, and the main valve along with other features hereof make this a unique and different regulator over the prior art, as will be seen in the specification hereinafter.